Test heads, such as those in U.S. Pat. Nos. 4,598,246 and 4,625,164, incorporated herein by reference, provide an interface by means of which electronic circuits are releasably reliably connected to automatic testing equipment operative to determine the integrity of the components, and cooperation between components, of the circuits.
A material disadvantage with the prior art test heads is a limitation in the speed with which the testing can be cyclically accomplished. One cause of the time delay has to do with the electrical path lengths. The longer the path lengths, the more time the electrical signal needs to propagate, the less the through-put of multiple devices to be tested. Another cause of the time delay is the transients induced by the capacitance, the inductance and other electrical properties of the wires, which transients must be allowed to settle before testing can proceed. Both effects depend directly on the total extension or length of the signal paths, and in the heretofore known testing heads, particularly those equipped for testing edge connector contacts of electric circuit devices, the wire lengths often are on the order of a full foot and one-half in length, which correlates with several milliseconds of lost time per cycle, and which represents undesirable if not unacceptable through-put delays.